Truing-gage.



G. W. WALDRIP & G. D. POPE.

TRUING GAGE.

' APPLICATION IILIJD SEPT. 19. 1907.

Patented Feb. 23, 1909.

INVENTOR$ CHARLES WWALDEIP [21: an G-E D P EI'FE ATTOHNEYS- UNITEDsnares PATENT @FFICE.

CHARLES W. WALDRIP AND GEORGE D. POPE, OF SAN PEDRO, CALIFORNIA.

TRUIN G-GA GE To all whom it may concern:

Be it known that we, CHARLES WV. \VAL- DRIP and GEORGE D. Porn, citizensof the United States, and residents of San Pedro, in the county of LosAngeles and State of California, have invented certain new and usefulImprovements in Truing-Gages, of which the following is a specification.

This invention is in the nature of a device for gaging the back edge ofsaws, particularly the back-edge of band saws, and has for its object, anew and improved device which shallnot only be portable in character,but simple in construction and effective in use for application to theback edge of a band saw, while it is in place on the bench.

It is well known that with a band saw, to obtain the best results itshould be convex on its back edge. It is further known that due toconstant, or prolonged use, and through sharpening operations of a saw,its front or cutting edge, becomes longer than the back edge, andthereby rendering the back edge into dished or concave form wherefromthe saw is rendered practically useless.

The prime object of our invention is to provide a portable deviceadapted for testing the back edge of a band, or similar saw, while it isin use on the machine, or removed therefrom as the occasion may be, andto the end stated we have invented the improved truing gage, shown bythe accorn anying drawing, and hereinafter fully descri )ed, the

features of novelty being pointed out in the ap ended claims.

11 the drawing, Figure 1 is a view illustrating the use of our improvedtruing gage. Fig. 2 is an enlarged view of the truing gage. Fig. 3 is abottom edge view of our truing gage, and Fig. 4 is a perspective view ofa modified form of the hand or pointer, forming a art of our invention.

In t e practice of our invention we employ an elongated bar A, havingparallel longitudinal side edges, substantially as shown.

To facilitate handling of our truing gage, we arrange handles B, on thebar A, preferably locating one thereof near each end of the bar, asillustrated by our drawing. On the bar A we provide a hand, or pointer Cand pivotally attach one end F thereof to a block, or bracket D rigidlysecured on one side of the bar A, or the block D may be integral withthe bar, as obviously would be within the scope of the invention. Thehand or pointer C is forced to swing on its pivotal Specification ofLetters Patent.

App1ication filed September 19, 1907.

Patented Feb. 23, 1909.

Serial No. 393,728.

attachment, b means of a projecting spring E secured to t 1e block orbracket D, and arranged with its other end bearing on the upper side ofthe pointer C, as shown, but 0 viously we do not restrict ourselves tosuch particular form of spring tension, as the same may be variouslyconstructed and in fact, in some instances or particular use of thetruing gage, the pointer may be con structed to operate simply bygravity. The sto s or pins J are as wide as the thickness of t 1e bar soas to engage with the saw blade at all times but the lug H extends onlypart way to the top of the bar so as to permit of the saw blade restingupon it and thereby being held up in position for being engaged by thepointer.

In the preferred construction of the pointer C, we provide it with alateral projection G, adapted to engage the rear edge of a saw beingtrued or gaged, said projection G being located near the pivoted end ofthe pointer or hand, substantially as shown. In the lower edge of thebar A we provide a recess G, adapted to receive the projecting pin G, asbest shown by Fig. 3. To facilitate application of our improved gage tothe thin edge of saw-blades, we provide an outwardly projecting off-setlug H, at its lower edge, and at the ends of the bar A, we arrange lugs,or projecting pins J, adapted to contact or rest against the back edgeof the saw-blade. In further carrying out our invention, an index orscale I is located on the blade A, adjacent to the path described by thefree end of the hand or pointer C.

The construction of our improved truing gage will be understood from theabove description, and its use being well understood, a detail statementthereof appears unnecessary, further than to say that when it is desiredto test a saw, the gage is placed against the back edge thereof as shownby Fig. 1, and slide therealong the whole length of the saw, or anyportion thereof which it is desired to test to ascertain if thesaw-blade is out of true. Any convexity or concavity formed along itsback edge will be indicated by the ointer C in its move ment along thegra uated scale I on the blade A. Use of our truing gage is materiallyfacilitated by revision thereon of the handles B, and the ugs J at theend of the bar A insures oro er testing engagement of the gage with t 1eack edge of the saw, that is, thereby the bar A is properly positionedon the saw, for effective engagement therewith, of the pin G on thepointer O.

Outward movement of the hand C is limited by a stop-pin L suitablylocated on the bar A. The pin is located at such a point relative tothe'scale that when the pointer is in engagement with a saw it will beheld away from the pin with its free end intermediate the ends of thescale and adjacent to what we will call the zero or normal point, whichis indicated in the drawings by extending one of the lines of the scalebeyond the others as indicated at N. By arranging the parts in thismanner the pointer is free to move upon either side of the normal whenits pivoted end engages with the saw and will thereby indicate whetherthe saw is concave or convex, and how much, but

when the instrument is not in use the spring will cause the free end ofthe pointer to move outward into engagement with the pin and therebyhold the pivoted end in position for being placed in engagement with theedge of the saw when the instrument is to be used. When the edge of thesaw is concave the pointer will stand at a point between the normal, orline N of the scale, and the pin L, but when it is convex, as isgenerally the case, it will stand beyond the normal. This increases theutility of the instrument and enables the saw filer to remove thecurvature in either direction and bring the saw back to the normal,which could not be done if there were no means rovided for detecting theconcavity of its e ge.

In Fig. 4 of our drawing we show a hand or pointer C more simplyconstructed than the pointer 0 shown in the other views of the drawing.In the modified form of ointer C itis constructed with an extension 2whose end C is bent transversely, ada ted to serve the purpose of theprojection on the hand or pointer C.

We claim: 1. In a truing gage, a bar provided with a transverse recessin one edge and a scale on one side adjacent to saidrecess, projectionson the recessed edge of the bar, the top of some of which is below theside of the bar provided with the scale, a pointer pivotally secured tothe bar and provided with means and a scale on one side, projections onthe recessed edge of the bar, a block on the side of the bar adjacent tothe said recess, a pointer pivotally secured to said block with its freeend adapted to be moved over said scale and provided with a projectionadapted to extend into said recess and be engaged by the edge of a sawwhen it is resting against said projections, a stop adjacent to saidscale, and a spring in engagement with the pointer to normally hold itagainst said stop.

3. In a truing gage, a portable bar provided with a scale upon one sideand with a recess in one edge and with means for positioning a sawvertically and laterally relatively to said recess, a ointer pivotallysecured to the bar with its iee end adjacent to the scale and itsintermediate portion provided with means for extending into said recessin position for being engaged by the edge of a saw when engaging withsaid ositioning means, a spring for normally forcing the free end of thepointer toward the recessed edge of the bar, a stop for limiting saidmovement, and a handle on the bar for moving it.

CHARLES W. VVALDRIP. GEORGE D. POPE. /Vitnesses:

JAMES WEIR, EDWIN B. MOORES.

